Mere minutes into the screening of “Jack Reacher” Monday night, a wave of pained groans rolled through the packed house. On screen, a sniper had set up across the river from the Pittsburgh Pirates’ ballpark. Through the crosshairs of his rifle scope we watched random people.

Mere minutes into the screening of “Jack Reacher” Monday night, a wave of pained groans rolled through the packed house.

On screen, a sniper had set up across the river from the Pittsburgh Pirates’ ballpark. Through the crosshairs of his rifle scope we watched random people:

A man on a bench.

A blonde in a black dress.

A woman carrying some legal folders.

A young woman walking, holding hands with a girl who looked about 6 years old.

For the moment, just days after the killings in Newtown, Conn., we were unwilling accomplices.

The sniper on the screen breathed. He squeezed the trigger. He squeezed it again, and again, and again, and again, and again.

A full auditorium may have never been quieter.

“Jack Reacher” is an average-to-good thriller. It’s brutal, snappy and a little long.

And its timing couldn’t have been worse.

Jack Reacher is the star of 18 crime novels and two short stories by Lee Child (look for the author in a cameo as a police desk clerk). Each paperback is 400-plus pages. They are addictive, breezy, hard-boiled, violent, suspenseful and ridiculous. They’re so manly the ink on the pages could be laced with raw testosterone.

Reacher is a former military policeman, traveling across the country, righting wrongs, exacting justice. He lives off the grid. Pays cash. Beds beautiful women, most of them cops or lawyers.

The movie, starring Tom Cruise, is based mostly on “One Shot,” about a military sniper framed for five murders. After the police arrest and question James Barr (Joseph Sikora) they hand him a typed confession. He takes a pen and writes three words: “Get Jack Reacher.”

Barr, who knew Reacher from the Army, thinks he will find the real shooter. Reacher wants to make sure Barr goes down, not only for these crimes but for murders he committed in Iraq.

Fans of the books have blogged incessantly about the casting of Cruise. Reacher is supposed to be blond, between 210 and 250 pounds, 6-foot-5.

Cruise, at 5-foot-7, is two inches shorter than co-star Rosamund Pike, who plays Barr’s attorney.

Through the magic of cinema, you’d never know it. Cruise may not have Reacher’s size, but he has his presence. He’s confident. In control. Men fear him. Women look at him as if they’ve lost their car keys down his pants.

The movie may capture the character, but the execution is occasionally sloppy. There are several infodumps — scenes of exposition explaining backstories, motives and situations. In other spots, the script intends to make the dialogue crackle, rat-a-tat-tat. Some of it works, as when a young woman in a bar hits on Reacher

“I can’t afford you,” Reacher says.

Offended, she protests: “I’m not a hooker.”

“Then I really can’t afford you,” he says.

But there’s no spark between the leads. Cruise and Pike look as if they’re just saying lines and occasionally talking over one another.

Pike has only two expressions in this role: wide-eyed and really wide-eyed. And her motivation to defend Barr is never very clear, unless it’s just to thumb her nose at her daddy, a district attorney played by Richard Jenkins.

There are nice moments. Reacher whoops five townies in an alley fight. The camera is set up on the periphery, holding for longer shots, eliminating the need for quick-cut editing and the illusion of motion. The trading of blows seems real and raw.

The big car chase through the streets of Pittsburgh looks truly dangerous. It helps that Cruise did much of the driving. Credit goes to director Christopher McQuarrie and Oscar-winning cinematographer Caleb Deschanel. Shame on them for crashing such a beautiful 1970 Chevelle (or, more likely, more than one) in the making of it.

Like “The Dark Knight Rises,” however, “Jack Reacher” is a casualty of current events. Reality intrudes. Scenes at shooting ranges, a witness statement describing the “pop, pop, pop” at the crime scene and bad guys laying down automatic weapon fire aren’t appealing now.

But consider this: Five characters are murdered on screen in the first five minutes, a young woman played by 20-year-old Alexia Fast is punched in the face and suffocated, Reacher bludgeons a thug in the head with another thug’s head, a stoolie is forced to choose between chewing off his fingers and taking a bullet to the brain, and it’s rated PG-13.

Of course, the books are more violent than the movie, and anyone of any age can buy the latest installment almost anywhere.

The only contingent more silent than the National Rifle Association this past week has been Hollywood and the entertainment industry. Presumably, they’re laying low, hoping not to hear that Adam Lanza repeatedly streamed “The Expendables” on Netflix or spent hours on Xbox Live blasting other players of “Modern Warfare.”

It’s easy for the recent events to turn us all into knee-jerkers and reactionaries. More often than not, movies are a catharsis, an escape from the real world.

But this is the wrong time for “Jack Reacher.” The more unfortunate truth of that sentence is there likely will come a right time for the film, months, weeks or even days from now.

And plenty more like it.

WHAT OTHERS ARE SAYING

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Ann Hornaday, Washington Post:

“Presumably taking a long, self-indulgent glance at his What Would Clint Do? bracelet, Tom Cruise takes on the iconic role of surly vigilante, resulting in a mismatch of wincingly epic proportions.”

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Christy Lemire, The Associated Press:

“Besides being caught in some unfortunate timing, it’s also clever, well-crafted and darkly humorous, and it features one of those effortless bad-ass performances from Tom Cruise that remind us that he is indeed a movie star, first and foremost.”

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Richard Corliss, Time: “It’s also disappointing when the film’s modest pleasures are scuttled by more sizable frustrations, and when a little movie with big talent behind it turns out to be suitable only for in-flight viewing.”